Abstract: This study analyzes the current state of thermal light sources-incandescent halogen lamps that are highly intense light sources which enables them to occupy a niche in the modern lighting technology. It reveals the advantages and benefits of these light sources, describes their operating principles and classification. We have been studied the features of the tungsten-halogen cycle in the halogen lamps that is capable of preventing from blackening shell with the tungsten evaporating from the luminous element, keeping it clean and clear throughout the lamp life cycle, described the conditions and the course of the cycle and its efficiency, the principles of selecting the composition and pressure of the filling gas mixture in the production of the halogen lamps. The elements of gas mixture, the components of chemical reactions may be in atomic or molecular state and form various binary and ternary compounds that have influence on the tungsten-halogen cycle and heat processes in the lamp. The transfer processes of heat and mass in the halogen bulbs are in turn, connected with engineering, operational and design data of these lighting sources. It has been shown that the parameter optimization of the halogen lamps must comprise search for new constructive solutions, optimum filling mixtures, ways to reduce heat losses in the filling gas. We have determined the problem aspects of developing the halogen lamps and main tendencies in their study. One of the tendencies of improvement of these lighting sources is minimization of heat losses and transport rate of the filament element in active volume. We have formulated the problems and their possible solutions which will enable to make design of the incandescent halogen lamps of maximum cost-effectiveness.